/* ============================================
   Material Design 3 - CSS Variables & Theme
   ============================================ */
:root {
    /* Material Design 3 Primary Color (Indigo) */
    --md-primary: #6750A4;
    --md-primary-container: #EADDFF;
    --md-on-primary: #FFFFFF;
    --md-on-primary-container: #21005D;
    
    /* Material Design 3 Surface Colors - Dark */
    --md-surface: #1C1B1F;
    --md-surface-container: #211F26;
    --md-surface-container-high: #2B2930;
    --md-surface-container-highest: #36343B;
    --md-on-surface: #E6E1E5;
    --md-on-surface-variant: #CAC4D0;
    
    /* Material Design 3 Outline */
    --md-outline: #938F99;
    --md-outline-variant: #49454F;
    
    /* Material Design 3 Elevation Shadows (Dark Theme) */
    --md-elevation-0: none;
    --md-elevation-1: 0px 1px 2px 0px rgba(0, 0, 0, 0.3), 0px 1px 3px 1px rgba(0, 0, 0, 0.15); /* 1dp */
    --md-elevation-2: 0px 1px 2px 0px rgba(0, 0, 0, 0.3), 0px 2px 6px 2px rgba(0, 0, 0, 0.15); /* 3dp */
    --md-elevation-3: 0px 1px 3px 0px rgba(0, 0, 0, 0.3), 0px 4px 8px 3px rgba(0, 0, 0, 0.15); /* 6dp */
    --md-elevation-4: 0px 2px 3px 0px rgba(0, 0, 0, 0.3), 0px 6px 10px 4px rgba(0, 0, 0, 0.15); /* 8dp */
    --md-elevation-5: 0px 4px 4px 0px rgba(0, 0, 0, 0.3), 0px 8px 12px 6px rgba(0, 0, 0, 0.15); /* 12dp */
    
    /* Legacy variables for compatibility */
    --primary: var(--md-primary);
    --primary-hover: #7C6BA8;
    --text: var(--md-on-surface);
    --text-secondary: var(--md-on-surface-variant);
    --bg: var(--md-surface);
    --container-bg: var(--md-surface-container);
    --input-bg: var(--md-surface-container-high);
    --border: var(--md-outline-variant);
    --button-bg: var(--md-surface-container-high);
}

:root[data-theme="light"] {
    /* Material Design 3 Primary Color (Indigo) - Light */
    --md-primary: #6750A4;
    --md-primary-container: #EADDFF;
    --md-on-primary: #FFFFFF;
    --md-on-primary-container: #21005D;
    
    /* Material Design 3 Surface Colors - Light */
    --md-surface: #FFFBFE;
    --md-surface-container: #F7F2FA;
    --md-surface-container-high: #F1ECF5;
    --md-surface-container-highest: #EBE6EF;
    --md-on-surface: #1C1B1F;
    --md-on-surface-variant: #49454F;
    
    /* Material Design 3 Outline - Light */
    --md-outline: #79747E;
    --md-outline-variant: #CAC4D0;
    
    /* Material Design 3 Elevation Shadows - Light */
    --md-elevation-0: none;
    --md-elevation-1: 0px 1px 3px 0px rgba(0, 0, 0, 0.12), 0px 1px 2px 0px rgba(0, 0, 0, 0.24); /* 1dp */
    --md-elevation-2: 0px 2px 6px 2px rgba(0, 0, 0, 0.15), 0px 1px 2px 0px rgba(0, 0, 0, 0.3); /* 3dp */
    --md-elevation-3: 0px 4px 8px 3px rgba(0, 0, 0, 0.15), 0px 1px 3px 0px rgba(0, 0, 0, 0.3); /* 6dp */
    --md-elevation-4: 0px 6px 10px 4px rgba(0, 0, 0, 0.15), 0px 2px 3px 0px rgba(0, 0, 0, 0.3); /* 8dp */
    --md-elevation-5: 0px 8px 12px 6px rgba(0, 0, 0, 0.15), 0px 4px 4px 0px rgba(0, 0, 0, 0.3); /* 12dp */
    
    /* Legacy variables */
    --primary-hover: #5A4A8F;
    --text: var(--md-on-surface);
    --text-secondary: var(--md-on-surface-variant);
    --bg: var(--md-surface);
    --container-bg: var(--md-surface-container);
    --input-bg: var(--md-surface);
    --border: var(--md-outline-variant);
    --button-bg: var(--md-surface-container-high);
}

/* ============================================
   Reset & Base Styles
   ============================================ */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: 'Roboto', 'Heebo', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: var(--md-surface);
    color: var(--md-on-surface);
    height: 100vh;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 40px;
    line-height: 1.5;
    animation: fadeIn 0.3s cubic-bezier(0.2, 0, 0, 1);
    font-size: 16px; /* Body Large base */
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

/* ============================================
   Container - Material Card
   ============================================ */
.container {
    position: relative;
    width: 100%;
    max-width: 640px;
    background: var(--md-surface-container);
    border-radius: 28px;
    padding: 40px;
    box-shadow: var(--md-elevation-2); /* 3dp elevation for cards (Material standard) */
    border: none;
    max-height: 100vh;
    overflow-y: auto;
    overflow-x: hidden;
    scrollbar-width: thin;
    scrollbar-color: var(--md-outline-variant) transparent;
    display: flex;
    flex-direction: column;
    animation: slideUp 0.4s cubic-bezier(0.2, 0, 0, 1);
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(24px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Material Design Scrollbar */
.container::-webkit-scrollbar {
    width: 8px;
}

.container::-webkit-scrollbar-track {
    background: transparent;
    margin: 8px 0;
}

.container::-webkit-scrollbar-thumb {
    background-color: var(--md-outline-variant);
    border-radius: 20px;
    border: 2px solid transparent;
    background-clip: padding-box;
    transition: background-color 0.2s cubic-bezier(0.2, 0, 0, 1);
}

.container::-webkit-scrollbar-thumb:hover {
    background-color: var(--md-outline);
}

/* ============================================
   Typography - Material Design 3
   ============================================ */
h2 {
    color: var(--md-on-surface);
    font-size: 2rem; /* Headline Large: 32sp */
    font-weight: 400;
    line-height: 1.25; /* 40sp / 32sp */
    margin-bottom: 0.5rem;
    text-align: center;
    letter-spacing: 0;
    background: none;
    -webkit-text-fill-color: var(--md-on-surface);
    animation: fadeInDown 0.4s cubic-bezier(0.2, 0, 0, 1) 0.1s both;
}

@keyframes fadeInDown {
    from {
        opacity: 0;
        transform: translateY(-8px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.subtitle-wrapper {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
    margin-bottom: 2rem;
    animation: fadeInDown 0.4s cubic-bezier(0.2, 0, 0, 1) 0.15s both;
}

.subtitle {
    text-align: center;
    color: var(--md-on-surface-variant);
    margin-bottom: 0;
    font-size: 0.875rem; /* Body Medium: 14sp */
    font-weight: 400;
    line-height: 1.43; /* 20sp / 14sp */
    letter-spacing: 0.25px;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

/* Help buttons - Material Outlined Button */
.help-buttons {
    display: flex;
    gap: 12px;
    justify-content: center;
    margin-top: 2rem;
    flex-wrap: wrap;
}

.help-button {
    background: transparent;
    border: 1px solid var(--md-outline);
    color: var(--md-primary);
    font-size: 0.875rem;
    font-weight: 500;
    padding: 10px 24px;
    border-radius: 20px;
    cursor: pointer;
    transition: all 0.2s cubic-bezier(0.2, 0, 0, 1);
    font-family: inherit;
    letter-spacing: 0.1px;
    text-transform: none;
    position: relative;
    overflow: hidden;
}

.help-button::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: var(--md-primary);
    opacity: 0.12;
    transform: translate(-50%, -50%);
    transition: width 0.3s cubic-bezier(0.2, 0, 0, 1), height 0.3s cubic-bezier(0.2, 0, 0, 1);
}

.help-button:hover::before {
    width: 600px;
    height: 600px;
}

.help-button:hover {
    border-color: var(--md-primary);
    background: rgba(103, 80, 164, 0.08);
}

.help-button:active {
    background: rgba(103, 80, 164, 0.12);
}

/* Required indicator */
.required-indicator {
    color: var(--md-primary);
    font-weight: 500;
    margin-right: 4px;
}

/* Field hint */
.field-hint {
    display: block;
    font-size: 0.75rem; /* Body Small: 12sp */
    color: var(--md-on-surface-variant);
    margin-top: 4px;
    padding-right: 4px;
    font-weight: 400;
    line-height: 1.33; /* 16sp / 12sp */
    letter-spacing: 0.4px;
}

/* ============================================
   Form Elements - Material Design 3
   ============================================ */
.form-group {
    margin-bottom: 1.5rem;
    background: transparent;
    padding: 0;
    border-radius: 0;
    transition: all 0.2s cubic-bezier(0.2, 0, 0, 1);
    position: relative;
    animation: fadeInUp 0.4s cubic-bezier(0.2, 0, 0, 1) both;
}

.form-group:nth-child(1) { animation-delay: 0.1s; }
.form-group:nth-child(2) { animation-delay: 0.15s; }
.form-group:nth-child(3) { animation-delay: 0.2s; }
.form-group:nth-child(4) { animation-delay: 0.25s; }
.form-group:nth-child(5) { animation-delay: 0.3s; }

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(8px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

label {
    display: block;
    margin-bottom: 4px;
    font-weight: 500;
    color: var(--md-on-surface);
    font-size: 0.875rem; /* Label Large: 14sp */
    line-height: 1.43; /* 20sp / 14sp */
    padding-right: 0;
    letter-spacing: 0.1px;
}

input, textarea {
    width: 100%;
    padding: 16px;
    font-size: 1rem; /* Body Large: 16sp */
    line-height: 1.5; /* 24sp / 16sp */
    background: var(--md-input-bg, var(--md-surface-container-high));
    border: 1px solid var(--md-outline-variant);
    border-radius: 4px; /* Material Design 3 standard */
    transition: all 0.2s cubic-bezier(0.2, 0, 0, 1);
    color: var(--md-on-surface);
    font-family: inherit;
    box-shadow: none;
    font-weight: 400;
    letter-spacing: 0.5px;
}

input:hover, textarea:hover {
    border-color: var(--md-on-surface);
    background: var(--md-input-bg, var(--md-surface-container-high));
}

input:focus, textarea:focus {
    outline: none;
    border-color: var(--md-primary);
    border-width: 2px;
    background: var(--md-input-bg, var(--md-surface-container-high));
    box-shadow: 0 0 0 1px var(--md-primary);
}

textarea {
    height: 100px;
    resize: vertical;
    min-height: 100px;
}

input::placeholder,
textarea::placeholder {
    color: var(--md-on-surface-variant);
    opacity: 1;
}

:root[dir="ltr"] input::placeholder,
:root[dir="ltr"] textarea::placeholder {
    text-align: left;
}

:root[dir="rtl"] input::placeholder,
:root[dir="rtl"] textarea::placeholder {
    text-align: right;
}

/* ============================================
   Buttons - Material Design 3
   ============================================ */
.buttons-container {
    margin-top: 2rem;
    position: relative;
    min-height: 48px;
}

.buttons {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
}

button {
    padding: 10px 24px;
    font-size: 0.875rem; /* Label Large: 14sp */
    font-weight: 500;
    line-height: 1.43; /* 20sp / 14sp */
    border-radius: 20px;
    cursor: pointer;
    transition: all 0.2s cubic-bezier(0.2, 0, 0, 1);
    font-family: inherit;
    position: relative;
    overflow: hidden;
    letter-spacing: 0.1px;
    text-transform: none;
    min-height: 40px;
    border: none;
}

/* Outlined Button (Mailto) */
button:first-child {
    color: var(--md-primary);
    background: transparent;
    border: 1px solid var(--md-outline);
    box-shadow: none;
}

button:first-child::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: var(--md-primary);
    opacity: 0.12;
    transform: translate(-50%, -50%);
    transition: width 0.3s cubic-bezier(0.2, 0, 0, 1), height 0.3s cubic-bezier(0.2, 0, 0, 1);
}

button:first-child:hover::before {
    width: 400px;
    height: 400px;
}

button:first-child:hover {
    border-color: var(--md-primary);
    background: rgba(103, 80, 164, 0.08);
    box-shadow: none;
}

button:first-child:active {
    background: rgba(103, 80, 164, 0.12);
}

/* Filled Button (Gmail) */
button:last-child {
    color: var(--md-on-primary);
    background: var(--md-primary);
    border: none;
    font-weight: 500;
    box-shadow: var(--md-elevation-1); /* 1dp elevation (Material Filled Button standard) */
}

button:last-child::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: var(--md-on-primary);
    opacity: 0.2;
    transform: translate(-50%, -50%);
    transition: width 0.3s cubic-bezier(0.2, 0, 0, 1), height 0.3s cubic-bezier(0.2, 0, 0, 1);
}

button:last-child:hover::before {
    width: 400px;
    height: 400px;
}

button:last-child:hover {
    background: var(--primary-hover);
    box-shadow: var(--md-elevation-2);
}

button:last-child:active {
    box-shadow: var(--md-elevation-1);
}

button:active {
    transform: scale(0.98);
}

button:disabled {
    opacity: 0.38;
    cursor: not-allowed;
    pointer-events: all !important;
}

button:disabled:hover {
    transform: none;
}

button:disabled::before {
    display: none;
}

button:disabled:hover::after {
    content: attr(data-tooltip);
    position: absolute;
    bottom: calc(100% + 8px);
    left: 50%;
    transform: translateX(-50%);
    background: var(--md-surface-container-highest);
    color: var(--md-on-surface);
    padding: 8px 12px;
    border-radius: 4px;
    font-size: 0.75rem;
    white-space: nowrap;
    pointer-events: none;
    opacity: 1;
    z-index: 1;
    animation: tooltipFadeIn 0.2s cubic-bezier(0.2, 0, 0, 1);
    box-shadow: var(--md-elevation-2);
}

@keyframes tooltipFadeIn {
    from {
        opacity: 0;
        transform: translateX(-50%) translateY(-4px);
    }
    to {
        opacity: 1;
        transform: translateX(-50%) translateY(0);
    }
}

button:disabled:hover::before {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 50%;
    transform: translateX(-50%);
    border-left: 4px solid transparent;
    border-right: 4px solid transparent;
    border-top: 4px solid var(--md-surface-container-highest);
}

/* Add fields button - Material Text Button */
.add-fields-button {
    background: transparent;
    border: none;
    color: var(--md-primary);
    font-size: 0.875rem;
    padding: 8px 12px;
    margin: 0 auto 16px;
    border-radius: 20px;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 8px;
    transition: all 0.2s cubic-bezier(0.2, 0, 0, 1);
    width: fit-content;
    font-weight: 500;
    letter-spacing: 0.1px;
    position: relative;
    overflow: hidden;
}

.add-fields-button::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: var(--md-primary);
    opacity: 0.12;
    transform: translate(-50%, -50%);
    transition: width 0.3s cubic-bezier(0.2, 0, 0, 1), height 0.3s cubic-bezier(0.2, 0, 0, 1);
}

.add-fields-button:hover::before {
    width: 300px;
    height: 300px;
}

.add-fields-button:hover {
    background: rgba(103, 80, 164, 0.08);
}

.add-fields-button:active {
    background: rgba(103, 80, 164, 0.12);
}

.add-fields-button svg {
    width: 20px;
    height: 20px;
    transition: transform 0.3s cubic-bezier(0.2, 0, 0, 1);
}

.add-fields-button.active svg {
    transform: rotate(180deg);
}

/* ============================================
   Additional Fields
   ============================================ */
.additional-fields {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s cubic-bezier(0.2, 0, 0, 1);
}

.additional-fields.visible {
    max-height: 300px;
}

/* ============================================
   Copy Status - Material Snackbar
   ============================================ */
#copyStatus {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%) scale(0.9);
    background: var(--md-surface-container-highest);
    color: var(--md-on-surface);
    padding: 16px 24px;
    border-radius: 16px;
    font-size: 0.875rem;
    font-weight: 500;
    opacity: 0;
    transition: all 0.3s cubic-bezier(0.2, 0, 0, 1);
    box-shadow: var(--md-elevation-5);
    pointer-events: none;
    letter-spacing: 0.1px;
    z-index: 2000;
    min-width: 200px;
    text-align: center;
}

#copyStatus.show {
    opacity: 1;
    transform: translate(-50%, -50%) scale(1);
    animation: snackbarSlideIn 0.3s cubic-bezier(0.2, 0, 0, 1);
}

@keyframes snackbarSlideIn {
    0% {
        opacity: 0;
        transform: translate(-50%, -50%) scale(0.9);
    }
    50% {
        transform: translate(-50%, -50%) scale(1.05);
    }
    100% {
        opacity: 1;
        transform: translate(-50%, -50%) scale(1);
    }
}

/* ============================================
   Scrollable Content
   ============================================ */
.scrollable-content {
    flex: 1;
    overflow-y: auto;
    margin: 0 -8px;
    padding: 0 8px;
}

.buttons-section {
    margin-top: 1.5rem;
    padding-top: 1.5rem;
    position: relative;
    background: var(--md-surface-container);
}

.buttons-section::before {
    content: '';
    position: absolute;
    top: 0;
    left: -40px;
    right: -40px;
    height: 1px;
    background: var(--md-outline-variant);
    animation: expandLine 0.4s cubic-bezier(0.2, 0, 0, 1) 0.3s both;
}

@keyframes expandLine {
    from {
        transform: scaleX(0);
    }
    to {
        transform: scaleX(1);
    }
}

/* ============================================
   Modal / Dialog - Material Design 3
   ============================================ */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.4);
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
    z-index: 1000;
    opacity: 0;
    visibility: hidden;
    transition: all 0.2s cubic-bezier(0.2, 0, 0, 1);
}

.modal-overlay.active {
    opacity: 1;
    visibility: visible;
}

.modal {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%) scale(0.95);
    background: var(--md-surface-container);
    border-radius: 28px;
    box-shadow: var(--md-elevation-5);
    border: none;
    max-width: 560px;
    width: 90%;
    max-height: 85vh;
    overflow-y: auto;
    z-index: 1001;
    opacity: 0;
    visibility: hidden;
    transition: all 0.2s cubic-bezier(0.2, 0, 0, 1);
}

.modal.active {
    opacity: 1;
    visibility: visible;
    transform: translate(-50%, -50%) scale(1);
    animation: modalSlideIn 0.2s cubic-bezier(0.2, 0, 0, 1);
}

@keyframes modalSlideIn {
    from {
        opacity: 0;
        transform: translate(-50%, -50%) scale(0.95) translateY(-8px);
    }
    to {
        opacity: 1;
        transform: translate(-50%, -50%) scale(1) translateY(0);
    }
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 24px;
    border-bottom: 1px solid var(--md-outline-variant);
    position: sticky;
    top: 0;
    background: var(--md-surface-container);
    border-radius: 28px 28px 0 0;
    z-index: 1;
}

.modal-header h3 {
    margin: 0;
    font-size: 1.5rem; /* Headline Small: 24sp */
    font-weight: 400;
    line-height: 1.33; /* 32sp / 24sp */
    color: var(--md-on-surface);
    letter-spacing: 0;
}

.modal-close {
    background: transparent;
    border: none;
    color: var(--md-on-surface-variant);
    font-size: 1.5rem;
    line-height: 1;
    cursor: pointer;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 20px;
    transition: all 0.2s cubic-bezier(0.2, 0, 0, 1);
    padding: 0;
    position: relative;
    overflow: hidden;
}

.modal-close::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: var(--md-on-surface);
    opacity: 0.12;
    transform: translate(-50%, -50%);
    transition: width 0.3s cubic-bezier(0.2, 0, 0, 1), height 0.3s cubic-bezier(0.2, 0, 0, 1);
}

.modal-close:hover::before {
    width: 200px;
    height: 200px;
}

.modal-close:hover {
    color: var(--md-on-surface);
    background: transparent;
}

.modal-close:active {
    background: rgba(0, 0, 0, 0.12);
}

.modal-content {
    padding: 24px;
    color: var(--md-on-surface);
    line-height: 1.5;
}

.modal-content p {
    margin-bottom: 1rem;
    color: var(--md-on-surface-variant);
    font-size: 0.875rem; /* Body Medium: 14sp */
    font-weight: 400;
    line-height: 1.43; /* 20sp / 14sp */
    letter-spacing: 0.25px;
}

.modal-content ul {
    margin: 1rem 0;
    padding-right: 24px;
    list-style-type: disc;
}

.modal-content li {
    margin-bottom: 0.5rem;
    color: var(--md-on-surface-variant);
    font-size: 0.875rem; /* Body Medium: 14sp */
    line-height: 1.43; /* 20sp / 14sp */
    letter-spacing: 0.25px;
}

.modal-content li:last-child {
    margin-bottom: 0;
}

/* Intro text in modal */
.modal-content .intro-text {
    margin-bottom: 1.5rem;
    padding-bottom: 1.5rem;
    border-bottom: 1px solid var(--md-outline-variant);
}

.modal-content .intro-text p {
    margin-bottom: 1rem;
    font-size: 0.875rem;
    line-height: 1.5;
}

.modal-content .intro-text p:last-child {
    margin-bottom: 0;
}

/* How to use section */
.modal-content .how-to-use {
    margin-top: 1.5rem;
}

.modal-content .how-to-use strong {
    display: block;
    color: var(--md-primary);
    font-size: 0.875rem;
    margin-bottom: 0.75rem;
    font-weight: 500;
    letter-spacing: 0.1px;
}

/* Explanation items inside modal */
.modal-content .explanation-item {
    margin-bottom: 1.25rem;
}

.modal-content .explanation-item:last-child {
    margin-bottom: 0;
}

/* Modal scrollbar */
.modal::-webkit-scrollbar {
    width: 8px;
}

.modal::-webkit-scrollbar-track {
    background: transparent;
}

.modal::-webkit-scrollbar-thumb {
    background-color: var(--md-outline-variant);
    border-radius: 20px;
    border: 2px solid transparent;
    background-clip: padding-box;
}

.modal::-webkit-scrollbar-thumb:hover {
    background-color: var(--md-outline);
}

.explanation-item {
    margin-bottom: 1rem;
}

.explanation-item:last-child {
    margin-bottom: 0;
}

.explanation-item strong {
    color: var(--md-primary);
    display: block;
    margin-bottom: 8px;
    font-size: 0.875rem;
    font-weight: 500;
    letter-spacing: 0.1px;
}

/* Recommendation item */
.explanation-item.recommendation {
    background: var(--md-primary-container);
    border: none;
    border-radius: 12px;
    padding: 16px;
    margin-bottom: 1.25rem;
}

.explanation-item.recommendation strong {
    color: var(--md-on-primary-container);
    font-size: 0.875rem;
    margin-bottom: 8px;
}

.explanation-item.recommendation p {
    margin: 0;
    font-size: 0.875rem;
    line-height: 1.5;
    color: var(--md-on-primary-container);
    letter-spacing: 0.25px;
}

.explanation-item ul {
    margin: 8px 0 0 0;
    padding-right: 20px;
    list-style-type: disc;
}

.explanation-item li {
    margin-bottom: 4px;
    font-size: 0.875rem;
    letter-spacing: 0.25px;
}

.explanation-item li:last-child {
    margin-bottom: 0;
}

/* ============================================
   Footer - Material Design 3
   ============================================ */
.footer {
    position: fixed;
    bottom: 16px;
    left: 0;
    right: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    text-align: center;
    font-size: 0.875rem;
    color: var(--md-on-surface-variant);
    z-index: 10;
    pointer-events: none;
    animation: fadeInUp 0.4s cubic-bezier(0.2, 0, 0, 1) 0.4s both;
    font-weight: 400;
    letter-spacing: 0.25px;
}

.footer p {
    background: var(--md-surface-container);
    padding: 8px 16px;
    border-radius: 16px;
    box-shadow: var(--md-elevation-1);
    border: none;
    pointer-events: all;
}

.footer a {
    color: var(--md-primary);
    text-decoration: none;
    transition: color 0.2s cubic-bezier(0.2, 0, 0, 1);
    font-weight: 500;
}

.footer a:hover {
    color: var(--primary-hover);
    text-decoration: underline;
}

.footer .separator {
    margin: 0 8px;
    opacity: 0.6;
}

/* ============================================
   Validation Tooltip
   ============================================ */
.validation-tooltip {
    position: absolute;
    bottom: calc(100% + 8px);
    right: 0;
    background: var(--md-surface-container-highest);
    color: var(--md-on-surface);
    padding: 8px 12px;
    border-radius: 4px;
    font-size: 0.75rem;
    opacity: 0;
    visibility: hidden;
    transition: all 0.2s cubic-bezier(0.2, 0, 0, 1);
    white-space: nowrap;
    pointer-events: none;
    box-shadow: var(--md-elevation-2);
    font-weight: 400;
    letter-spacing: 0.25px;
}

.validation-tooltip::after {
    content: '';
    position: absolute;
    bottom: -4px;
    right: 10px;
    border-left: 4px solid transparent;
    border-right: 4px solid transparent;
    border-top: 4px solid var(--md-surface-container-highest);
}

.validation-tooltip.show {
    opacity: 1;
    visibility: visible;
    transform: translateY(-4px);
}

/* ============================================
   Responsive Design
   ============================================ */
@media (max-width: 640px) {
    body {
        padding: 16px;
        height: 100dvh;
        align-items: flex-start;
    }
    
    .container {
        padding: 24px 16px;
        border-radius: 24px;
        transform: none;
        max-height: calc(100dvh - 32px);
    }

    h2 {
        font-size: 1.5rem;
        margin-top: 32px;
    }
    
    .subtitle {
        font-size: 0.8125rem;
        margin-bottom: 1.5rem;
    }
    
    .help-buttons {
        gap: 8px;
        margin-top: 1.5rem;
    }
    
    .help-button {
        font-size: 0.8125rem;
        padding: 8px 16px;
    }
    
    .modal {
        width: 95%;
        max-height: 90vh;
        border-radius: 24px;
    }
    
    .modal-header {
        padding: 20px;
    }
    
    .modal-header h3 {
        font-size: 1.25rem;
    }
    
    .modal-content {
        padding: 20px;
    }
    
    .modal-content .intro-text {
        margin-bottom: 1.25rem;
        padding-bottom: 1.25rem;
    }
    
    .modal-content .intro-text p {
        font-size: 0.8125rem;
    }
    
    .modal-content .how-to-use strong {
        font-size: 0.8125rem;
    }

    .form-group {
        margin-bottom: 1rem;
    }
    
    .field-hint {
        font-size: 0.7rem;
        margin-top: 4px;
    }
    
    input, textarea {
        padding: 14px;
        font-size: 16px; /* Prevents zoom on iOS */
    }
    
    textarea {
        height: 80px;
        min-height: 80px;
    }

    .buttons {
        grid-template-columns: 1fr;
        gap: 12px;
    }
    
    button {
        padding: 10px 16px;
        font-size: 0.875rem;
        min-height: 40px;
    }
    
    .buttons-section {
        margin-top: 1rem;
        padding-top: 1rem;
    }

    .buttons-section::before {
        left: -16px;
        right: -16px;
    }
    
    .explanation-item strong {
        font-size: 0.8125rem;
    }
    
    .explanation-item.recommendation {
        padding: 12px;
        margin-bottom: 1rem;
    }
    
    .explanation-item.recommendation strong {
        font-size: 0.8125rem;
    }
    
    .explanation-item.recommendation p {
        font-size: 0.8125rem;
    }
    
    .explanation-item li {
        font-size: 0.8125rem;
    }

    .container::-webkit-scrollbar {
        width: 4px;
    }

    #copyStatus {
        top: 50%;
        padding: 14px 20px;
        font-size: 0.875rem;
        min-width: 180px;
    }

    .add-fields-button {
        padding: 8px 12px;
        font-size: 0.8125rem;
        margin: 0.5rem auto;
    }

    .scrollable-content {
        margin: 0 -4px;
        padding: 0 4px;
    }

    input::placeholder,
    textarea::placeholder {
        font-size: 0.875rem;
    }

    .footer {
        bottom: 8px;
    }
    
    .footer p {
        padding: 6px 12px;
        font-size: 0.8125rem;
    }
}