/* ═══════════════════════════════════════════════════════════════════
   Habit Tracker — Liquid Glass Design System
   Telegram 2025 Premium Dark UI
   ═══════════════════════════════════════════════════════════════════ */

:root {
    /* ── Backgrounds ── */
    --bg-void: #050507;
    --bg-primary: #0A0B0D;
    --bg-surface: #111214;
    --bg-elevated: #18191D;
    --bg-card: #1C1D22;

    /* ── Glass ── */
    --glass-bg: rgba(255, 255, 255, 0.03);
    --glass-bg-hover: rgba(255, 255, 255, 0.05);
    --glass-bg-active: rgba(255, 255, 255, 0.07);
    --glass-border: rgba(255, 255, 255, 0.08);
    --glass-border-light: rgba(255, 255, 255, 0.12);
    --glass-border-strong: rgba(255, 255, 255, 0.18);
    --glass-shadow: 0 8px 32px rgba(0, 0, 0, 0.5);
    --glass-shadow-lg: 0 16px 48px rgba(0, 0, 0, 0.6);
    --glass-blur: blur(24px);
    --glass-blur-heavy: blur(40px);

    /* ── Accent Colors ── */
    --accent: #2AABEE;
    --accent-hover: #3BB5F0;
    --accent-dim: rgba(42, 171, 238, 0.12);
    --accent-glow: rgba(42, 171, 238, 0.2);
    --accent-glow-strong: rgba(42, 171, 238, 0.4);
    --ton-blue: #0098EA;
    --premium-purple: #8B5CF6;
    --premium-glow: rgba(139, 92, 246, 0.2);

    /* ── Semantic ── */
    --success: #10B981;
    --success-dim: rgba(16, 185, 129, 0.12);
    --success-glow: rgba(16, 185, 129, 0.25);
    --warning: #F59E0B;
    --warning-dim: rgba(245, 158, 11, 0.12);
    --danger: #EF4444;
    --danger-dim: rgba(239, 68, 68, 0.12);
    --fire: #F97316;
    --fire-dim: rgba(249, 115, 22, 0.12);

    /* ── Text ── */
    --text-primary: #FFFFFF;
    --text-secondary: #A1A1AA;
    --text-tertiary: #71717A;
    --text-muted: #52525B;

    /* ── Layout ── */
    --radius-xs: 8px;
    --radius-sm: 12px;
    --radius-md: 16px;
    --radius-lg: 20px;
    --radius-xl: 24px;
    --radius-2xl: 28px;
    --radius-full: 9999px;
    --safe-bottom: env(safe-area-inset-bottom, 0px);

    /* ── Spacing ── */
    --space-xs: 4px;
    --space-sm: 8px;
    --space-md: 12px;
    --space-lg: 16px;
    --space-xl: 20px;
    --space-2xl: 24px;
    --space-3xl: 32px;
}

/* ═══════════════════ Reset & Base ═══════════════════ */

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    -webkit-tap-highlight-color: transparent;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'SF Pro Display',
                 'SF Pro Text', system-ui, sans-serif;
    background: var(--bg-void);
    color: var(--text-primary);
    direction: rtl;
    min-height: 100vh;
    min-height: 100dvh;
    padding-bottom: calc(88px + var(--safe-bottom));
    overflow-x: hidden;
    font-size: 15px;
    line-height: 1.5;
    letter-spacing: -0.01em;
}

/* ═══════════════════ Typography ═══════════════════ */

.text-display {
    font-size: 42px;
    font-weight: 800;
    letter-spacing: -0.04em;
    line-height: 1.1;
}

.text-title-lg {
    font-size: 22px;
    font-weight: 700;
    letter-spacing: -0.02em;
}

.text-title {
    font-size: 17px;
    font-weight: 600;
    letter-spacing: -0.02em;
}

.text-body {
    font-size: 15px;
    font-weight: 400;
}

.text-caption {
    font-size: 13px;
    font-weight: 500;
}

.text-micro {
    font-size: 11px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.06em;
}

/* ═══════════════════ Liquid Glass Surfaces ═══════════════════ */

.glass {
    background: var(--glass-bg);
    backdrop-filter: var(--glass-blur);
    -webkit-backdrop-filter: var(--glass-blur);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-lg);
    box-shadow: var(--glass-shadow);
}

.glass-card {
    background: linear-gradient(
        135deg,
        rgba(255, 255, 255, 0.04) 0%,
        rgba(255, 255, 255, 0.01) 100%
    );
    backdrop-filter: var(--glass-blur);
    -webkit-backdrop-filter: var(--glass-blur);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-xl);
    box-shadow:
        var(--glass-shadow),
        inset 0 1px 0 rgba(255, 255, 255, 0.05);
    position: relative;
    overflow: hidden;
}

.glass-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(
        90deg,
        transparent 0%,
        rgba(255, 255, 255, 0.1) 50%,
        transparent 100%
    );
    pointer-events: none;
}

.glass-surface {
    background: var(--bg-surface);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-lg);
}

.glass-inset {
    background: rgba(0, 0, 0, 0.2);
    border: 1px solid rgba(255, 255, 255, 0.04);
    border-radius: var(--radius-md);
}

/* ═══════════════════ Liquid Glass Buttons ═══════════════════ */

.btn-glass {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 14px 24px;
    background: linear-gradient(
        135deg,
        rgba(255, 255, 255, 0.08) 0%,
        rgba(255, 255, 255, 0.03) 100%
    );
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid var(--glass-border-light);
    border-radius: var(--radius-full);
    color: var(--text-primary);
    font-size: 15px;
    font-weight: 600;
    font-family: inherit;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
    position: relative;
    overflow: hidden;
    -webkit-user-select: none;
    user-select: none;
    box-shadow:
        0 4px 16px rgba(0, 0, 0, 0.3),
        inset 0 1px 0 rgba(255, 255, 255, 0.08);
}

.btn-glass::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(
        135deg,
        rgba(255, 255, 255, 0.1) 0%,
        transparent 60%
    );
    opacity: 0;
    transition: opacity 0.3s ease;
    pointer-events: none;
}

.btn-glass:hover::before,
.btn-glass:active::before {
    opacity: 1;
}

.btn-glass:active {
    transform: scale(0.96);
    box-shadow:
        0 2px 8px rgba(0, 0, 0, 0.4),
        inset 0 1px 0 rgba(255, 255, 255, 0.06);
}

.btn-glass svg {
    width: 18px;
    height: 18px;
}

/* ── Primary Accent Button ── */
.btn-accent {
    background: linear-gradient(
        135deg,
        var(--accent) 0%,
        var(--ton-blue) 100%
    );
    border: 1px solid rgba(42, 171, 238, 0.3);
    color: #fff;
    box-shadow:
        0 4px 20px rgba(42, 171, 238, 0.25),
        inset 0 1px 0 rgba(255, 255, 255, 0.15);
}

.btn-accent:active {
    box-shadow:
        0 2px 12px rgba(42, 171, 238, 0.3),
        inset 0 1px 0 rgba(255, 255, 255, 0.1);
}

/* ── Success Button ── */
.btn-success {
    background: linear-gradient(135deg, #10B981 0%, #059669 100%);
    border: 1px solid rgba(16, 185, 129, 0.3);
    color: #fff;
    box-shadow:
        0 4px 20px rgba(16, 185, 129, 0.2),
        inset 0 1px 0 rgba(255, 255, 255, 0.15);
}

/* ── Small Button ── */
.btn-sm {
    padding: 10px 18px;
    font-size: 14px;
    border-radius: var(--radius-sm);
}

/* ── Full Width Button ── */
.btn-block {
    width: 100%;
}

/* ═══════════════════ Pages ═══════════════════ */

.page {
    display: none;
    padding: 0 0 var(--space-xl);
}

.page.active {
    display: block;
}

/* ═══════════════════ Sections ═══════════════════ */

.section {
    margin-bottom: var(--space-xl);
}

.section-header {
    padding: var(--space-sm) var(--space-xl) var(--space-md);
    font-size: 11px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--text-tertiary);
}

.section-card {
    margin: 0 var(--space-lg);
    background: var(--bg-surface);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-xl);
    overflow: hidden;
}

/* ═══════════════════ Spacing Utilities ═══════════════════ */

.mx-lg { margin-left: var(--space-lg); margin-right: var(--space-lg); }
.mb-sm { margin-bottom: var(--space-sm); }
.mb-md { margin-bottom: var(--space-md); }
.mb-lg { margin-bottom: var(--space-lg); }
.mb-xl { margin-bottom: var(--space-xl); }
.p-lg { padding: var(--space-lg); }
.p-xl { padding: var(--space-xl); }

/* ═══════════════════ Toast ═══════════════════ */

.toast {
    position: fixed;
    top: 20px;
    left: 50%;
    transform: translateX(-50%) translateY(-100px);
    background: var(--bg-elevated);
    color: var(--text-primary);
    padding: 12px 24px;
    border-radius: var(--radius-full);
    font-size: 14px;
    font-weight: 600;
    z-index: 9999;
    border: 1px solid var(--glass-border-light);
    box-shadow: var(--glass-shadow-lg);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    white-space: nowrap;
    transition: transform 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
}

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

/* ═══════════════════ Empty State ═══════════════════ */

.empty-state {
    text-align: center;
    padding: 48px var(--space-xl);
    color: var(--text-tertiary);
    font-size: 15px;
}