:root {
    --bg-main: #0a0e17;
    --bg-surface: #121927;
    --bg-surface-elevated: #182235;
    --bg-surface-hover: #1f2c45;
    --border-color: #24324d;
    --border-glow: rgba(99, 102, 241, 0.25);
    
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;

    --primary: #6366f1;
    --primary-hover: #4f46e5;
    --primary-glow: rgba(99, 102, 241, 0.4);
    
    --accent: #06b6d4;
    --success: #10b981;
    --warning: #f59e0b;
    --danger: #ef4444;

    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 18px;
    --radius-full: 9999px;

    --transition: all 0.2s cubic-bezier(0.16, 1, 0.3, 1);
    --shadow-card: 0 10px 30px -10px rgba(0, 0, 0, 0.5), 0 0 0 1px var(--border-color);
    --shadow-glow: 0 0 35px -5px var(--primary-glow);
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    -webkit-font-smoothing: antialiased;
}

body {
    background-color: var(--bg-main);
    color: var(--text-primary);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    line-height: 1.5;
    overflow-x: hidden;
    background-image: 
        radial-gradient(circle at 15% 15%, rgba(99, 102, 241, 0.12) 0%, transparent 40%),
        radial-gradient(circle at 85% 65%, rgba(6, 182, 212, 0.09) 0%, transparent 45%);
}

.container {
    width: 100%;
    max-width: 900px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header */
.app-header {
    border-bottom: 1px solid var(--border-color);
    background: rgba(10, 14, 23, 0.75);
    backdrop-filter: blur(12px);
    position: sticky;
    top: 0;
    z-index: 50;
}

.header-inner {
    height: 70px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
    text-decoration: none;
    color: var(--text-primary);
}

.logo-icon {
    width: 38px;
    height: 38px;
    border-radius: var(--radius-md);
    background: linear-gradient(135deg, var(--primary), var(--accent));
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 4px 12px var(--primary-glow);
}

.logo-text {
    font-size: 1.25rem;
    font-weight: 700;
    letter-spacing: -0.02em;
    display: flex;
    align-items: center;
    gap: 8px;
}

.badge-live {
    font-size: 0.65rem;
    text-transform: uppercase;
    font-weight: 700;
    padding: 2px 7px;
    border-radius: var(--radius-full);
    background: rgba(16, 185, 129, 0.15);
    color: var(--success);
    border: 1px solid rgba(16, 185, 129, 0.3);
    letter-spacing: 0.05em;
    display: inline-flex;
    align-items: center;
    gap: 4px;
}

.badge-live::before {
    content: '';
    width: 6px;
    height: 6px;
    background: var(--success);
    border-radius: 50%;
    box-shadow: 0 0 6px var(--success);
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; transform: scale(1); }
    50% { opacity: 0.4; transform: scale(0.85); }
}

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

.btn-secondary-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 8px 14px;
    border-radius: var(--radius-sm);
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.875rem;
    font-weight: 500;
    border: 1px solid var(--border-color);
    background: var(--bg-surface);
    transition: var(--transition);
}

.btn-secondary-link:hover {
    color: var(--text-primary);
    border-color: var(--primary);
    background: var(--bg-surface-elevated);
}

/* Main Content */
main {
    flex: 1;
    padding: 40px 0 60px;
}

/* Hero Section */
.hero {
    text-align: center;
    margin-bottom: 36px;
}

.hero h1 {
    font-size: 2.5rem;
    font-weight: 800;
    letter-spacing: -0.03em;
    margin-bottom: 12px;
    background: linear-gradient(135deg, #ffffff 40%, #94a3b8 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero p {
    color: var(--text-secondary);
    font-size: 1.1rem;
    max-width: 580px;
    margin: 0 auto;
}

/* Card Common */
.card {
    background: var(--bg-surface);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-card);
    padding: 30px;
    margin-bottom: 28px;
    border: 1px solid var(--border-color);
    position: relative;
    overflow: hidden;
}

.card-glow::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 2px;
    background: linear-gradient(90deg, transparent, var(--primary), var(--accent), transparent);
}

/* Shortener Form */
.form-group {
    margin-bottom: 18px;
}

.input-with-button {
    display: flex;
    gap: 8px;
    background: var(--bg-main);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 6px;
    transition: var(--transition);
}

.input-with-button:focus-within {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px var(--border-glow);
}

.url-input {
    flex: 1;
    background: transparent;
    border: none;
    outline: none;
    color: var(--text-primary);
    font-size: 1rem;
    padding: 10px 14px;
}

.url-input::placeholder {
    color: var(--text-muted);
}

.btn-icon-action {
    background: transparent;
    border: none;
    color: var(--text-secondary);
    padding: 8px 12px;
    border-radius: var(--radius-sm);
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 0.825rem;
    transition: var(--transition);
}

.btn-icon-action:hover {
    color: var(--text-primary);
    background: var(--bg-surface-elevated);
}

/* Advanced Options */
.options-toggle {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    background: none;
    border: none;
    color: var(--text-secondary);
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    margin-bottom: 16px;
    transition: var(--transition);
}

.options-toggle:hover {
    color: var(--text-primary);
}

.options-toggle .chevron {
    transition: transform 0.2s ease;
}

.options-toggle.open .chevron {
    transform: rotate(180deg);
}

.options-panel {
    display: none;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
    padding: 16px;
    background: var(--bg-main);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    margin-bottom: 20px;
}

.options-panel.visible {
    display: grid;
    animation: fadeIn 0.2s ease;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(-4px); }
    to { opacity: 1; transform: translateY(0); }
}

.option-field label {
    display: block;
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 6px;
    text-transform: uppercase;
    letter-spacing: 0.04em;
}

.text-input, .select-input {
    width: 100%;
    background: var(--bg-surface);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    color: var(--text-primary);
    padding: 10px 12px;
    font-size: 0.9rem;
    outline: none;
    transition: var(--transition);
}

.text-input:focus, .select-input:focus {
    border-color: var(--primary);
}

.option-hint {
    font-size: 0.75rem;
    color: var(--text-muted);
    margin-top: 4px;
}

/* Submit Button */
.btn-primary {
    width: 100%;
    background: linear-gradient(135deg, var(--primary), #4338ca);
    color: #ffffff;
    border: none;
    border-radius: var(--radius-md);
    padding: 14px 24px;
    font-size: 1.05rem;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    box-shadow: 0 4px 14px var(--primary-glow);
    transition: var(--transition);
}

.btn-primary:hover {
    filter: brightness(1.1);
    transform: translateY(-1px);
    box-shadow: 0 6px 20px var(--primary-glow);
}

.btn-primary:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

/* Alert Notification */
.alert {
    display: none;
    padding: 12px 16px;
    border-radius: var(--radius-sm);
    font-size: 0.9rem;
    margin-bottom: 20px;
    align-items: center;
    gap: 10px;
}

.alert.visible {
    display: flex;
}

.alert-danger {
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid rgba(239, 68, 68, 0.3);
    color: #fca5a5;
}

.alert-success {
    background: rgba(16, 185, 129, 0.1);
    border: 1px solid rgba(16, 185, 129, 0.3);
    color: #86efac;
}

/* Result Section */
.result-card {
    display: none;
    animation: slideUp 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

.result-card.visible {
    display: block;
}

@keyframes slideUp {
    from { opacity: 0; transform: translateY(16px); }
    to { opacity: 1; transform: translateY(0); }
}

.result-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 20px;
}

.result-badge {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    color: var(--success);
    font-weight: 600;
    font-size: 0.95rem;
}

.result-box {
    display: flex;
    align-items: center;
    justify-content: space-between;
    background: var(--bg-main);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 14px 18px;
    margin-bottom: 20px;
    gap: 12px;
}

.short-url-link {
    color: var(--accent);
    font-size: 1.15rem;
    font-weight: 700;
    text-decoration: none;
    word-break: break-all;
    transition: var(--transition);
}

.short-url-link:hover {
    text-decoration: underline;
}

.result-actions {
    display: flex;
    align-items: center;
    gap: 8px;
    flex-shrink: 0;
}

.btn-action {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    background: var(--bg-surface-elevated);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    padding: 8px 14px;
    border-radius: var(--radius-sm);
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    text-decoration: none;
}

.btn-action:hover {
    border-color: var(--primary);
    background: var(--bg-surface-hover);
}

.btn-action.copied {
    background: var(--success);
    border-color: var(--success);
    color: #ffffff;
}

/* QR Code Section */
.qr-container {
    display: none;
    padding-top: 20px;
    border-top: 1px solid var(--border-color);
    text-align: center;
    animation: fadeIn 0.2s ease;
}

.qr-container.visible {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.qr-canvas-wrapper {
    background: #ffffff;
    padding: 12px;
    border-radius: var(--radius-md);
    display: inline-block;
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.4);
    margin-bottom: 14px;
}

#qrCanvas {
    display: block;
}

.qr-actions {
    display: flex;
    gap: 10px;
}

/* History Section */
.history-section {
    margin-top: 40px;
}

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

.history-title {
    font-size: 1.25rem;
    font-weight: 700;
    display: flex;
    align-items: center;
    gap: 8px;
}

.btn-clear-history {
    background: none;
    border: none;
    color: var(--text-muted);
    font-size: 0.8rem;
    cursor: pointer;
    transition: var(--transition);
}

.btn-clear-history:hover {
    color: var(--danger);
}

.history-list {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.history-item {
    background: var(--bg-surface);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 16px 20px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    transition: var(--transition);
}

.history-item:hover {
    border-color: var(--primary);
    background: var(--bg-surface-elevated);
}

.history-info {
    flex: 1;
    min-width: 0;
}

.history-short {
    font-weight: 600;
    font-size: 1rem;
    color: var(--accent);
    text-decoration: none;
    display: inline-block;
    margin-bottom: 4px;
}

.history-original {
    font-size: 0.825rem;
    color: var(--text-muted);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    display: block;
}

.history-meta {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-top: 6px;
    font-size: 0.75rem;
    color: var(--text-secondary);
}

.meta-pill {
    background: var(--bg-main);
    padding: 2px 8px;
    border-radius: var(--radius-full);
    border: 1px solid var(--border-color);
    display: inline-flex;
    align-items: center;
    gap: 4px;
}

.history-actions {
    display: flex;
    align-items: center;
    gap: 8px;
}

.empty-history {
    text-align: center;
    padding: 30px;
    background: var(--bg-surface);
    border: 1px dashed var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-muted);
    font-size: 0.9rem;
}

/* Toast Notification */
.toast {
    position: fixed;
    bottom: 24px;
    right: 24px;
    background: var(--bg-surface-elevated);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    padding: 12px 18px;
    border-radius: var(--radius-md);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.875rem;
    font-weight: 500;
    transform: translateY(100px);
    opacity: 0;
    transition: var(--transition);
    z-index: 100;
}

.toast.show {
    transform: translateY(0);
    opacity: 1;
}

/* Footer */
footer {
    border-top: 1px solid var(--border-color);
    padding: 24px 0;
    background: var(--bg-main);
    font-size: 0.85rem;
    color: var(--text-muted);
}

.footer-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.status-indicator {
    display: flex;
    align-items: center;
    gap: 6px;
}

.dot-green {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--success);
    box-shadow: 0 0 8px var(--success);
}

/* Responsive */
@media (max-width: 640px) {
    .hero h1 {
        font-size: 1.85rem;
    }
    .options-panel {
        grid-template-columns: 1fr;
    }
    .result-box {
        flex-direction: column;
        align-items: flex-start;
    }
    .result-actions {
        width: 100%;
        justify-content: space-between;
    }
    .history-item {
        flex-direction: column;
        align-items: flex-start;
    }
    .history-actions {
        width: 100%;
        justify-content: flex-end;
    }
    .footer-inner {
        flex-direction: column;
        gap: 12px;
        text-align: center;
    }
}