/* ============================================
   Semaphore Flag Encoder — Design System
   ============================================ */

/* --- CSS Variables / Tokens --- */
:root {
    --bg-primary: #0B0E17;
    --bg-secondary: #12162A;
    --bg-card: rgba(22, 28, 50, 0.85);
    --bg-glass: rgba(22, 28, 50, 0.6);
    --border-glass: rgba(255, 255, 255, 0.08);
    --text-primary: #E8ECF4;
    --text-secondary: #8892B0;
    --text-muted: #5A6480;
    --accent: #6C63FF;
    --accent-glow: rgba(108, 99, 255, 0.3);
    --accent-hover: #7B73FF;
    --success: #4ADE80;
    --error: #F87171;
    --warning: #FBBF24;
    --flag-red: #E63946;
    --flag-yellow: #F4D35E;
    --flag-blue: #1D3557;
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 20px;
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.2);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.4);
    --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
    --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

[data-theme="light"] {
    --bg-primary: #F0F2F8;
    --bg-secondary: #FFFFFF;
    --bg-card: rgba(255, 255, 255, 0.9);
    --bg-glass: rgba(255, 255, 255, 0.7);
    --border-glass: rgba(0, 0, 0, 0.08);
    --text-primary: #1A1E2E;
    --text-secondary: #4A5568;
    --text-muted: #8892A8;
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.06);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.1);
}

/* --- Reset & Base --- */
*,
*::before,
*::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    overflow-x: hidden;
    transition: background var(--transition), color var(--transition);
}

/* Subtle animated background */
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background:
        radial-gradient(ellipse 600px 400px at 20% 30%, rgba(108, 99, 255, 0.06) 0%, transparent 70%),
        radial-gradient(ellipse 500px 300px at 80% 70%, rgba(232, 57, 70, 0.04) 0%, transparent 70%);
    pointer-events: none;
    z-index: -1;
}

/* --- App Container --- */
.app {
    max-width: 960px;
    margin: 0 auto;
    padding: 0 16px;
}

/* --- Header --- */
.header {
    padding: 20px 0 12px;
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
}

.logo-icon {
    font-size: 2rem;
    width: 52px;
    height: 52px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--accent), var(--flag-red));
    border-radius: var(--radius-md);
    box-shadow: 0 4px 16px var(--accent-glow);
}

.logo h1 {
    font-size: 1.3rem;
    font-weight: 700;
    letter-spacing: -0.02em;
    background: linear-gradient(135deg, var(--text-primary), var(--accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.tagline {
    font-size: 0.75rem;
    color: var(--text-muted);
    font-weight: 400;
    letter-spacing: 0.04em;
    text-transform: uppercase;
}

.header-actions {
    display: flex;
    gap: 8px;
}

/* --- Icon Button --- */
.icon-btn {
    width: 40px;
    height: 40px;
    border: none;
    background: var(--bg-glass);
    backdrop-filter: blur(12px);
    border: 1px solid var(--border-glass);
    border-radius: var(--radius-sm);
    color: var(--text-secondary);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition);
}

.icon-btn:hover {
    background: var(--bg-card);
    color: var(--accent);
    transform: translateY(-1px);
    box-shadow: var(--shadow-sm);
}

.icon {
    width: 18px;
    height: 18px;
}

/* Theme toggle icon visibility */
.moon-icon {
    display: none;
}

[data-theme="light"] .sun-icon {
    display: none;
}

[data-theme="light"] .moon-icon {
    display: block;
}

/* --- Tabs --- */
.tabs {
    display: flex;
    gap: 4px;
    padding: 4px;
    background: var(--bg-glass);
    backdrop-filter: blur(12px);
    border: 1px solid var(--border-glass);
    border-radius: var(--radius-lg);
    margin-bottom: 20px;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
}

.tab {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    padding: 10px 12px;
    border: none;
    background: transparent;
    color: var(--text-muted);
    font-family: var(--font);
    font-size: 0.82rem;
    font-weight: 500;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition);
    white-space: nowrap;
    min-width: 0;
}

.tab .icon {
    width: 16px;
    height: 16px;
    flex-shrink: 0;
}

.tab:hover {
    color: var(--text-secondary);
    background: rgba(108, 99, 255, 0.05);
}

.tab.active {
    background: var(--accent);
    color: #fff;
    box-shadow: 0 2px 12px var(--accent-glow);
}

/* --- Panels --- */
.panel {
    display: none;
    animation: fadeIn 0.3s ease;
}

.panel.active {
    display: block;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(8px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* --- Buttons --- */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 10px 20px;
    border: none;
    border-radius: var(--radius-sm);
    font-family: var(--font);
    font-size: 0.88rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition);
    white-space: nowrap;
}

.btn-primary {
    background: linear-gradient(135deg, var(--accent), #8B83FF);
    color: #fff;
    box-shadow: 0 2px 12px var(--accent-glow);
}

.btn-primary:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 20px var(--accent-glow);
}

.btn-secondary {
    background: var(--bg-glass);
    backdrop-filter: blur(8px);
    border: 1px solid var(--border-glass);
    color: var(--text-secondary);
}

.btn-secondary:hover {
    background: var(--bg-card);
    color: var(--text-primary);
    transform: translateY(-1px);
}

.btn-sm {
    padding: 6px 14px;
    font-size: 0.8rem;
}

.btn-text {
    background: none;
    border: none;
    color: var(--text-muted);
    font-family: var(--font);
    font-size: 0.8rem;
    cursor: pointer;
    padding: 4px 8px;
    border-radius: var(--radius-sm);
    transition: color var(--transition);
}

.btn-text:hover {
    color: var(--accent);
}

/* --- Input / Textarea --- */
textarea,
select {
    width: 100%;
    padding: 12px 16px;
    background: var(--bg-secondary);
    border: 1px solid var(--border-glass);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-family: var(--font);
    font-size: 0.92rem;
    resize: vertical;
    transition: border-color var(--transition), box-shadow var(--transition);
}

textarea:focus,
select:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 3px var(--accent-glow);
}

textarea::placeholder {
    color: var(--text-muted);
}

label {
    display: block;
    font-size: 0.82rem;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 6px;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

/* --- Encode Section --- */
.input-group {
    margin-bottom: 20px;
}

.input-row {
    display: flex;
    gap: 10px;
}

.input-row textarea {
    flex: 1;
}

.input-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 6px;
    font-size: 0.78rem;
    color: var(--text-muted);
}

.result-area {
    background: var(--bg-card);
    backdrop-filter: blur(16px);
    border: 1px solid var(--border-glass);
    border-radius: var(--radius-lg);
    padding: 20px;
    box-shadow: var(--shadow-md);
}

.result-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 16px;
}

.result-header h2 {
    font-size: 1rem;
    font-weight: 600;
}

.result-actions {
    display: flex;
    gap: 8px;
}

/* --- Flag Display (Semaphore) --- */
.flag-display {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    justify-content: center;
}

.flag-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
    padding: 8px;
    background: var(--bg-secondary);
    border: 1px solid var(--border-glass);
    border-radius: var(--radius-sm);
    min-width: 64px;
    transition: all var(--transition);
}

.flag-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-sm);
    border-color: var(--accent);
}

.flag-card.space {
    background: transparent;
    border: 1px dashed var(--border-glass);
    opacity: 0.5;
}

.flag-card .letter {
    font-size: 0.72rem;
    font-weight: 700;
    color: var(--accent);
    text-transform: uppercase;
}

.flag-card.highlight {
    border-color: var(--accent);
    box-shadow: 0 0 12px var(--accent-glow);
}

/* --- Semaphore Figure (SVG) --- */
.semaphore-figure {
    width: 56px;
    height: 56px;
}

.semaphore-figure.large {
    width: 140px;
    height: 140px;
}

/* --- Animation Player --- */
.animation-player {
    margin-top: 16px;
    padding: 20px;
    background: var(--bg-secondary);
    border-radius: var(--radius-md);
    text-align: center;
}

.player-controls {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    margin-bottom: 16px;
    flex-wrap: wrap;
}

.speed-control {
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 0.8rem;
    color: var(--text-secondary);
}

.speed-control input[type="range"] {
    width: 80px;
    accent-color: var(--accent);
}

.current-letter {
    font-size: 2rem;
    font-weight: 700;
    color: var(--accent);
    margin-bottom: 12px;
}

.semaphore-figure-container {
    display: flex;
    justify-content: center;
}

/* --- Decode Section --- */
.decode-controls {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
    align-items: start;
}

.decode-figure-wrap {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 16px;
}

.angle-selectors {
    display: flex;
    gap: 12px;
    width: 100%;
}

.angle-group {
    flex: 1;
}

.angle-group select {
    padding: 10px;
    font-size: 0.82rem;
}

.decode-output {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.decoded-char {
    font-size: 4rem;
    font-weight: 700;
    text-align: center;
    color: var(--accent);
    padding: 20px;
    background: var(--bg-secondary);
    border-radius: var(--radius-md);
    border: 1px solid var(--border-glass);
}

.decoded-message-area {
    margin-top: 8px;
}

.decoded-message {
    min-height: 48px;
    padding: 12px 16px;
    background: var(--bg-secondary);
    border: 1px solid var(--border-glass);
    border-radius: var(--radius-sm);
    font-family: 'Courier New', monospace;
    font-size: 1.1rem;
    letter-spacing: 0.08em;
    word-break: break-all;
    color: var(--text-primary);
}

/* --- Maritime Section --- */
.maritime-input-group {
    display: flex;
    gap: 10px;
    margin-bottom: 20px;
}

.maritime-input-group textarea {
    flex: 1;
}

.maritime-flags {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    justify-content: center;
    margin-bottom: 28px;
}

.maritime-flag-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 6px;
    padding: 10px;
    background: var(--bg-card);
    border: 1px solid var(--border-glass);
    border-radius: var(--radius-sm);
    transition: all var(--transition);
}

.maritime-flag-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-sm);
}

.maritime-flag-card svg {
    width: 48px;
    height: 48px;
}

.maritime-flag-card .flag-label {
    font-size: 0.72rem;
    font-weight: 700;
    color: var(--accent);
}

.ics-reference h3 {
    font-size: 0.95rem;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--text-primary);
}

.ics-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
    gap: 8px;
}

.ics-item {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 8px 12px;
    background: var(--bg-secondary);
    border-radius: var(--radius-sm);
    border: 1px solid var(--border-glass);
    font-size: 0.82rem;
}

.ics-item svg {
    width: 32px;
    height: 32px;
    flex-shrink: 0;
}

.ics-item .ics-letter {
    font-weight: 700;
    color: var(--accent);
    min-width: 16px;
}

.ics-item .ics-meaning {
    color: var(--text-secondary);
}

/* --- Quiz Section --- */
.quiz-controls {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    flex-wrap: wrap;
    gap: 10px;
}

.quiz-modes {
    display: flex;
    gap: 4px;
}

.quiz-mode {
    background: var(--bg-glass);
    border: 1px solid var(--border-glass);
    color: var(--text-muted);
}

.quiz-mode.active {
    background: var(--accent);
    color: #fff;
    border-color: var(--accent);
}

.quiz-stats {
    display: flex;
    gap: 16px;
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-secondary);
}

.quiz-area {
    text-align: center;
    padding: 24px;
    background: var(--bg-card);
    border: 1px solid var(--border-glass);
    border-radius: var(--radius-lg);
    backdrop-filter: blur(16px);
}

.quiz-question {
    display: flex;
    justify-content: center;
    margin-bottom: 16px;
}

.quiz-prompt {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 16px;
}

.quiz-options {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    justify-content: center;
    margin-bottom: 16px;
}

.quiz-option {
    padding: 10px 20px;
    background: var(--bg-secondary);
    border: 2px solid var(--border-glass);
    border-radius: var(--radius-sm);
    color: var(--text-primary);
    font-family: var(--font);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition);
    min-width: 52px;
}

.quiz-option:hover:not(:disabled) {
    border-color: var(--accent);
    background: rgba(108, 99, 255, 0.08);
    transform: translateY(-1px);
}

.quiz-option.correct {
    border-color: var(--success);
    background: rgba(74, 222, 128, 0.15);
    color: var(--success);
}

.quiz-option.wrong {
    border-color: var(--error);
    background: rgba(248, 113, 113, 0.15);
    color: var(--error);
}

.quiz-feedback {
    padding: 10px;
    border-radius: var(--radius-sm);
    font-weight: 600;
    font-size: 0.9rem;
    margin-bottom: 12px;
}

.quiz-feedback.correct {
    background: rgba(74, 222, 128, 0.1);
    color: var(--success);
}

.quiz-feedback.wrong {
    background: rgba(248, 113, 113, 0.1);
    color: var(--error);
}

.quiz-actions {
    display: flex;
    justify-content: center;
    gap: 10px;
}

/* --- Reference Grid --- */
.reference-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(100px, 1fr));
    gap: 10px;
}

.ref-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 6px;
    padding: 12px 8px;
    background: var(--bg-card);
    border: 1px solid var(--border-glass);
    border-radius: var(--radius-md);
    transition: all var(--transition);
}

.ref-card:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-md);
    border-color: var(--accent);
}

.ref-card .ref-letter {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--accent);
}

.ref-card .ref-desc {
    font-size: 0.65rem;
    color: var(--text-muted);
    text-align: center;
}

/* --- Toast --- */
.toast {
    position: fixed;
    bottom: 24px;
    left: 50%;
    transform: translateX(-50%) translateY(20px);
    padding: 12px 24px;
    background: var(--bg-card);
    backdrop-filter: blur(16px);
    border: 1px solid var(--border-glass);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-size: 0.88rem;
    font-weight: 500;
    box-shadow: var(--shadow-lg);
    opacity: 0;
    transition: all 0.35s ease;
    z-index: 100;
    pointer-events: none;
}

.toast.show {
    opacity: 1;
    transform: translateX(-50%) translateY(0);
}

/* --- Utility --- */
.hidden {
    display: none !important;
}

.subtitle {
    font-size: 0.88rem;
    color: var(--text-secondary);
    margin-bottom: 20px;
}

h2 {
    font-size: 1.15rem;
    font-weight: 700;
    margin-bottom: 4px;
}

/* --- Print Styles --- */
@media print {
    body {
        background: #fff;
        color: #000;
    }

    .header,
    .tabs,
    .input-group,
    .result-actions,
    .animation-player,
    .toast,
    .quiz-section,
    .decode-section,
    .maritime-input-group,
    .ics-reference {
        display: none !important;
    }

    .panel {
        display: block !important;
    }

    .flag-card,
    .ref-card {
        border: 1px solid #ccc;
        background: #fff;
        page-break-inside: avoid;
    }
}

/* --- Responsive --- */
@media (max-width: 640px) {
    .header-content {
        flex-wrap: wrap;
    }

    .logo h1 {
        font-size: 1.1rem;
    }

    .tabs {
        gap: 2px;
        padding: 3px;
    }

    .tab {
        padding: 8px 6px;
        font-size: 0.72rem;
        gap: 4px;
    }

    .tab .icon {
        width: 14px;
        height: 14px;
    }

    .input-row {
        flex-direction: column;
    }

    .decode-controls {
        grid-template-columns: 1fr;
    }

    .angle-selectors {
        flex-direction: column;
    }

    .reference-grid {
        grid-template-columns: repeat(auto-fill, minmax(80px, 1fr));
    }

    .ics-grid {
        grid-template-columns: 1fr;
    }

    .quiz-options {
        gap: 6px;
    }

    .quiz-option {
        padding: 8px 14px;
        font-size: 0.9rem;
        min-width: 42px;
    }
}