/* OptiLM Global Styles — v2 clean redesign */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&display=swap');

:root {
    /* Color System — Slate Teal: sophisticated, modern, clean */
    --primary: #0F172A;
    --accent: #0D9488;
    --accent-hover: #0F766E;
    --accent-light: #CCFBF1;
    --accent-subtle: rgba(13, 148, 136, 0.08);
    --bg: #F8FAFC;
    --surface: #FFFFFF;
    --text: #0F172A;
    --text-secondary: #64748B;
    --text-muted: #94A3B8;
    --border: #E2E8F0;
    --border-light: #F1F5F9;
    --success: #10b981;
    --error: #DC2626;

    /* Shadows — subtle, no color tint */
    --shadow-xs: 0 1px 2px rgba(0,0,0,0.04);
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.06);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.06);
    --shadow-lg: 0 8px 24px rgba(0,0,0,0.08);
    --shadow-xl: 0 16px 40px rgba(0,0,0,0.1);

    /* Radius */
    --radius-sm: 6px;
    --radius: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
    --radius-2xl: 20px;

    /* Transitions */
    --ease: cubic-bezier(0.4, 0, 0.2, 1);
    --transition-fast: 0.15s var(--ease);
    --transition: 0.2s var(--ease);

    /* Legacy compat — pages using old var names */
    --primary-color: var(--primary);
    --secondary-color: var(--accent);
    --accent-color: var(--accent);
    --background-color: var(--bg);
    --surface-color: var(--surface);
    --surface-elevated: var(--surface);
    --text-color: var(--text);
    --text-secondary: #64748B;
    --text-muted: #94A3B8;
    --border-color: var(--border);
    --border-light: var(--border-light);
    --gradient-primary: var(--accent);
    --gradient-secondary: var(--accent);
    --gradient-subtle: var(--accent-subtle);
    --gradient-dark: #0F172A;
    --shadow-glow: none;
    --border-radius-sm: var(--radius-sm);
    --border-radius: var(--radius);
    --border-radius-lg: var(--radius-lg);
    --border-radius-xl: var(--radius-xl);
    --border-radius-2xl: var(--radius-2xl);
}

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

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    scrollbar-gutter: stable;
    -webkit-tap-highlight-color: rgba(0, 0, 0, 0.06);
}

/* Ensure tap highlight is grey on all interactive elements — kills browser default blue */
a, button, input, select, textarea, [role="button"], [onclick] {
    -webkit-tap-highlight-color: rgba(0, 0, 0, 0.06);
}

html, body {
    width: 100%;
    max-width: 100vw;
    overflow-x: hidden;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: var(--bg);
    color: var(--text);
    min-height: 100vh;
    line-height: 1.6;
    display: flex;
    flex-direction: column;
    font-size: 15px;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.3;
    letter-spacing: -0.02em;
    color: var(--primary);
}

h1 { font-size: clamp(2rem, 4vw, 2.75rem); }
h2 { font-size: clamp(1.5rem, 3vw, 2rem); }
h3 { font-size: clamp(1.125rem, 2vw, 1.375rem); }

p { color: var(--text-secondary); line-height: 1.7; }

a {
    color: inherit;
    text-decoration: none;
    transition: color var(--transition-fast);
}

/* ==================== */
/* NAVIGATION           */
/* ==================== */
.global-nav {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0.75rem 1.5rem;
    display: flex;
    align-items: center;
    gap: 2rem;
}

.nav-logo {
    font-size: 1.25rem;
    font-weight: 800;
    color: var(--primary);
    text-decoration: none;
    letter-spacing: -0.03em;
    flex-shrink: 0;
}

.nav-logo:hover {
    color: var(--accent);
}

.nav-logo {
    -webkit-tap-highlight-color: transparent;
}

.nav-links {
    display: flex;
    gap: 0.25rem;
    align-items: center;
}

.nav-link {
    color: var(--text-secondary);
    font-weight: 500;
    font-size: 0.875rem;
    padding: 0.5rem 0.75rem;
    border-radius: var(--radius);
    transition: all var(--transition-fast);
}

.nav-link:hover {
    color: var(--text);
    background: var(--border-light);
}

.nav-link.active {
    color: var(--text);
    background: var(--border-light);
    font-weight: 600;
}

.nav-actions {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-left: auto;
}

/* Auth Buttons */
.auth-buttons {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.login-link {
    color: var(--text-secondary);
    font-weight: 500;
    font-size: 0.875rem;
    padding: 0.5rem 0.75rem;
    border-radius: var(--radius);
    transition: all var(--transition-fast);
}

.login-link:hover {
    color: var(--text);
    background: var(--border-light);
}

.register-btn {
    background: var(--primary);
    color: white;
    padding: 0.5rem 1rem;
    border-radius: var(--radius);
    font-weight: 600;
    font-size: 0.875rem;
    transition: all var(--transition-fast);
    border: none;
    cursor: pointer;
}

.register-btn:hover {
    background: #1E293B;
    transform: none;
    box-shadow: none;
}

/* User Info */
.user-info {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.user-name-link {
    display: flex;
    align-items: center;
    gap: 0.375rem;
    color: var(--text-secondary);
    font-weight: 500;
    font-size: 0.875rem;
    padding: 0.375rem 0.625rem;
    border-radius: var(--radius);
    transition: all var(--transition-fast);
    background: var(--border-light);
}

.user-name-link:hover { color: var(--text); }
.user-name-link svg { width: 16px; height: 16px; }

.nav-admin-link {
    color: var(--accent);
    font-weight: 500;
    font-size: 0.875rem;
    padding: 0.375rem 0.625rem;
    border-radius: var(--radius);
    background: var(--accent-light);
    transition: all var(--transition-fast);
}

.nav-admin-link:hover { background: #99F6E4; }

.logout-btn {
    background: transparent;
    color: var(--text-muted);
    padding: 0.375rem 0.625rem;
    border-radius: var(--radius);
    font-weight: 500;
    font-size: 0.875rem;
    border: 1px solid var(--border);
    cursor: pointer;
    box-shadow: none;
    transition: all var(--transition-fast);
}

.logout-btn:hover {
    border-color: var(--error);
    color: var(--error);
    transform: none;
    box-shadow: none;
    background: transparent;
}

/* Mobile Nav Toggle */
.nav-mobile-toggle {
    display: none;
    flex-direction: column;
    gap: 4px;
    cursor: pointer;
    padding: 0.5rem;
    border-radius: var(--radius-sm);
}

.nav-mobile-toggle span {
    width: 20px;
    height: 2px;
    background: var(--text);
    transition: all var(--transition-fast);
    border-radius: 1px;
}

.nav-mobile-toggle.active span:nth-child(1) { transform: rotate(45deg) translate(4px, 4px); }
.nav-mobile-toggle.active span:nth-child(2) { opacity: 0; }
.nav-mobile-toggle.active span:nth-child(3) { transform: rotate(-45deg) translate(4px, -4px); }

/* ==================== */
/* HOME PAGE            */
/* ==================== */
.home-container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 0 1.5rem;
    flex: 1;
}

.hero {
    text-align: center;
    padding: 4rem 0 3rem;
}

.hero::before { display: none; }

.hero-content {
    max-width: 680px;
    margin: 0 auto;
}

.hero-title {
    font-size: clamp(2.25rem, 5vw, 3rem);
    font-weight: 800;
    color: var(--primary);
    letter-spacing: -0.03em;
    line-height: 1.1;
    margin-bottom: 1rem;
    animation: fadeInUp 0.5s ease-out;
}

.gradient-text {
    color: var(--accent);
    background: none;
    -webkit-background-clip: unset;
    -webkit-text-fill-color: unset;
    background-clip: unset;
}

.hero-subtitle {
    font-size: 1.125rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
    max-width: 520px;
    margin-left: auto;
    margin-right: auto;
    line-height: 1.6;
    animation: fadeInUp 0.5s ease-out 0.1s backwards;
}

.hero-cta {
    display: flex;
    gap: 0.75rem;
    justify-content: center;
    flex-wrap: wrap;
    animation: fadeInUp 0.5s ease-out 0.15s backwards;
}

.btn-primary {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    background: var(--primary);
    color: white;
    padding: 0.75rem 1.5rem;
    border-radius: var(--radius);
    font-weight: 600;
    font-size: 0.9375rem;
    transition: all var(--transition-fast);
    border: none;
    cursor: pointer;
}

.btn-primary:hover {
    background: #1E293B;
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.btn-secondary {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    background: var(--surface);
    color: var(--text);
    padding: 0.75rem 1.5rem;
    border-radius: var(--radius);
    font-weight: 600;
    font-size: 0.9375rem;
    transition: all var(--transition-fast);
    border: 1px solid var(--border);
    cursor: pointer;
}

.btn-secondary:hover {
    border-color: var(--text-muted);
    transform: translateY(-1px);
    box-shadow: var(--shadow-sm);
}

/* ==================== */
/* FEATURE CARDS        */
/* ==================== */
.features { margin-bottom: 4rem; }

.features-header {
    text-align: center;
    margin-bottom: 2rem;
}

.features-header h2 {
    font-size: 0.8125rem;
    font-weight: 600;
    color: var(--accent);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    margin-bottom: 0.5rem;
}

.features-header p {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary);
    letter-spacing: -0.02em;
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1rem;
}

.feature-card {
    background: var(--surface);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    text-decoration: none;
    color: var(--text);
    transition: all var(--transition);
    border: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    cursor: pointer;
}

.feature-card::before { display: none; }
.feature-card::after { display: none; }
.feature-card > * { position: relative; z-index: 1; }

.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--border);
}

.feature-icon {
    width: 44px;
    height: 44px;
    background: var(--accent-light);
    border-radius: var(--radius);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1rem;
    color: var(--accent);
    transition: all var(--transition-fast);
}

.feature-card:hover .feature-icon {
    background: var(--accent);
    color: white;
    transform: none;
}

.feature-icon svg { width: 22px; height: 22px; }

.feature-title {
    font-size: 1.0625rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    color: var(--primary);
}

.feature-description {
    color: var(--text-secondary);
    margin-bottom: 1rem;
    flex-grow: 1;
    font-size: 0.875rem;
    line-height: 1.6;
}

.feature-action {
    color: var(--accent);
    font-weight: 600;
    font-size: 0.8125rem;
    display: inline-flex;
    align-items: center;
    gap: 0.375rem;
}

.feature-action::after { content: '→'; }
.feature-card:hover .feature-action { gap: 0.5rem; }

/* ==================== */
/* STATS SECTION        */
/* ==================== */
.stats-section {
    padding: 3rem 0;
    margin-bottom: 3rem;
    background: var(--primary);
    border-radius: var(--radius-xl);
    position: relative;
    overflow: hidden;
}

.stats-section::before { display: none; }

.stats-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
    max-width: 800px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

.stat-item { text-align: center; }

.stat-value {
    font-size: 2.5rem;
    font-weight: 800;
    color: white;
    letter-spacing: -0.03em;
    margin-bottom: 0.25rem;
    background: none;
    -webkit-background-clip: unset;
    -webkit-text-fill-color: white;
    background-clip: unset;
}

.stat-label {
    color: rgba(255, 255, 255, 0.6);
    font-size: 0.875rem;
    font-weight: 500;
}

/* ==================== */
/* FOOTER               */
/* ==================== */
.site-footer, .home-footer {
    background: var(--surface);
    border-top: 1px solid var(--border);
    padding: 1.5rem;
    margin-top: auto;
}

.site-footer .footer-content, .home-footer .footer-content {
    max-width: 1000px;
    margin: 0 auto;
    text-align: center;
    color: var(--text-muted);
    font-size: 0.8125rem;
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: 1.25rem;
    margin-top: 0.5rem;
}

.footer-links a {
    color: var(--text-muted);
    font-size: 0.8125rem;
}

.footer-links a:hover { color: var(--text-secondary); }

/* ==================== */
/* GLOBAL BUTTONS       */
/* ==================== */
button,
input[type="button"],
input[type="submit"],
input[type="reset"] {
    padding: 0.625rem 1.25rem;
    border: none;
    border-radius: var(--radius);
    font-size: 0.9375rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-fast);
    font-family: inherit;
    background: var(--primary);
    color: white;
    box-shadow: none;
}

button:hover,
input[type="button"]:hover,
input[type="submit"]:hover {
    background: #1E293B;
    transform: translateY(-1px);
    box-shadow: var(--shadow-sm);
}

button:active { transform: translateY(0); }
button:disabled { opacity: 0.5; cursor: not-allowed; transform: none; }

button.secondary {
    background: var(--surface);
    color: var(--text);
    border: 1px solid var(--border);
    box-shadow: none;
}

button.secondary:hover {
    border-color: var(--text-muted);
    box-shadow: var(--shadow-xs);
}

button.danger { background: var(--error); }

/* ==================== */
/* FORM INPUTS          */
/* ==================== */
input[type="text"],
input[type="email"],
input[type="password"],
input[type="search"],
textarea,
select {
    width: 100%;
    padding: 0.625rem 0.875rem;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    font-size: 0.9375rem;
    font-family: inherit;
    background: var(--surface);
    color: var(--text);
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

input:focus,
textarea:focus,
select:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 2px var(--accent-subtle);
}

/* ==================== */
/* ANIMATIONS           */
/* ==================== */
@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(16px); }
    to { opacity: 1; transform: translateY(0); }
}

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

.fade-in { animation: fadeIn 0.25s ease-out; }
.fade-in-up { animation: fadeInUp 0.4s ease-out; }

.feature-card:nth-child(1) { animation: fadeInUp 0.4s ease-out 0.05s backwards; }
.feature-card:nth-child(2) { animation: fadeInUp 0.4s ease-out 0.1s backwards; }
.feature-card:nth-child(3) { animation: fadeInUp 0.4s ease-out 0.15s backwards; }
.feature-card:nth-child(4) { animation: fadeInUp 0.4s ease-out 0.2s backwards; }

/* ==================== */
/* RESPONSIVE           */
/* ==================== */
@media (max-width: 1024px) {
    .feature-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
    .nav-container {
        padding: 0.625rem 1rem;
        gap: 0.75rem;
    }

    .nav-logo { font-size: 1.125rem; }

    .nav-links {
        display: none;
        position: fixed;
        top: 52px;
        left: 0;
        right: 0;
        background: var(--surface);
        flex-direction: column;
        padding: 0.75rem;
        border-bottom: 1px solid var(--border);
        box-shadow: var(--shadow-lg);
        z-index: 100;
        gap: 0.125rem;
        max-height: calc(100vh - 52px);
        overflow-y: auto;
    }

    .nav-links.mobile-active { display: flex; }

    .nav-link {
        padding: 0.75rem 0.875rem;
        width: 100%;
    }

    .nav-mobile-toggle { display: flex; order: 3; }
    .nav-actions { order: 2; margin-left: auto; }

    .auth-buttons { gap: 0.25rem; }
    .login-link { padding: 0.375rem 0.5rem; font-size: 0.75rem; }
    .register-btn { padding: 0.375rem 0.625rem; font-size: 0.75rem; }
    .user-info { gap: 0.25rem; }
    .user-name-link { padding: 0.25rem 0.375rem; font-size: 0.75rem; }
    .user-name-link span { display: none; }
    .logout-btn { padding: 0.25rem 0.375rem; font-size: 0.75rem; }
    .nav-admin-link { padding: 0.25rem 0.375rem; font-size: 0.75rem; }

    .hero { padding: 2rem 0 1.5rem; }
    .hero-title { font-size: 1.75rem; line-height: 1.15; }
    .hero-subtitle { font-size: 1rem; margin-bottom: 1.5rem; }

    .hero-cta {
        flex-direction: column;
        align-items: center;
        gap: 0.5rem;
    }

    .btn-primary, .btn-secondary {
        width: 100%;
        max-width: 260px;
        justify-content: center;
        padding: 0.625rem 1.25rem;
    }

    .features { margin-bottom: 2rem; }
    .features-header { margin-bottom: 1.5rem; }
    .features-header p { font-size: 1.25rem; }

    .feature-grid { grid-template-columns: 1fr; gap: 0.75rem; }
    .feature-card { padding: 1.25rem; }
    .feature-icon { width: 40px; height: 40px; margin-bottom: 0.75rem; }
    .feature-icon svg { width: 20px; height: 20px; }
    .feature-title { font-size: 1rem; }
    .feature-description { font-size: 0.8125rem; margin-bottom: 0.75rem; }

    .home-container { padding: 0 1rem; }

    .stats-section {
        border-radius: 0;
        margin-left: -1rem;
        margin-right: -1rem;
        padding: 2rem 0;
    }

    .stats-grid { grid-template-columns: 1fr; gap: 1.25rem; }
    .stat-value { font-size: 2rem; }
    .stat-label { font-size: 0.8125rem; }

    .site-footer, .home-footer { padding: 1.25rem 1rem; }

    input[type="text"],
    input[type="email"],
    input[type="password"],
    input[type="search"],
    textarea, select {
        font-size: 16px !important;
    }
}

@media (max-width: 380px) {
    .nav-container { padding: 0.5rem 0.75rem; }
    .nav-logo { font-size: 1rem; }
    .hero-title { font-size: 1.5rem; }
    .auth-buttons { gap: 0.125rem; }
    .login-link, .register-btn { padding: 0.25rem 0.375rem; font-size: 0.6875rem; }
}

/* ==================== */
/* UTILITIES            */
/* ==================== */
.hidden { display: none !important; }
.loading { opacity: 0.6; pointer-events: none; }
.text-center { text-align: center; }
.text-gradient { color: var(--accent); }