/* Nordic Theme & Typography */
:root {
    /* Mapped from ability.icu Palette */
    --fjord-blue: #005F73;
    --glacial-teal: #0A9396;
    --nordic-gold: #E9D8A6;
    --slate: #475569;
    --snow: #F8FAFC;
    --deep-forest: #121E2A;

    /* Light Theme (Default) Mapping */
    --bg-color: var(--snow);
    --surface-color: #ffffff;
    --text-primary: var(--deep-forest);
    --text-secondary: var(--slate);
    --border-color: #e2e8f0;
    --accent-color: var(--fjord-blue);
    --accent-hover: var(--glacial-teal);
    --error-bg: #fef2f2;
    --error-text: #991b1b;
    --divider: #f1f5f9;

    /* Layout */
    --radius-md: 8px;
    /* Slightly softer than before */
    --radius-lg: 12px;
    /* More rounded paper */
    --radius-full: 9999px;
    --shadow-paper: 0 4px 12px rgba(0, 0, 0, 0.05), 0 1px 2px rgba(0, 0, 0, 0.02);
    --transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Dark Theme Variables */
[data-theme="dark"] {
    /* Keep the structure but invert tones, maintaining the Fjord/Teal brand */
    --bg-color: #0f172a;
    /* Slate 900 */
    --surface-color: #1e293b;
    /* Slate 800 */
    --text-primary: #f8fafc;
    /* Snow */
    --text-secondary: #94a3b8;
    /* Slate 400 */
    --border-color: #334155;
    /* Slate 700 */
    --accent-color: var(--glacial-teal);
    /* Brighter accent for dark mode */
    --accent-hover: #4ade80;
    /* A brighter, energetic hover */
    --error-bg: #450a0a;
    --error-text: #fca5a5;
    --divider: #334155;
    --shadow-paper: 0 10px 15px -1px rgba(0, 0, 0, 0.4), 0 0 2px 1px rgba(0, 0, 0, 0.2);
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-primary);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 2rem 1rem;
    line-height: 1.6;
    transition: background-color var(--transition), color var(--transition);
}

h1,
h2,
h3,
h4,
h5,
h6 {
    font-weight: 500;
    line-height: 1.3;
    color: var(--text-primary);
    letter-spacing: -0.01em;
}

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

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

a:hover {
    color: var(--accent-hover);
    text-decoration: underline;
}

hr {
    border: none;
    border-top: 1px dashed var(--border-color);
    margin: 3rem 0;
}

/* Utilities & Components */
.max-w-md {
    width: 100%;
    max-width: 32rem;
    /* Slightly wider sheet */
}

/* "The Paper" / Cards */
.paper-container {
    background-color: var(--surface-color);
    border-radius: var(--radius-lg);
    box-shadow: none;
    /* Removing drop shadow in favor of clean border */
    border: 1px solid var(--border-color);
    padding: 2.5rem 2rem;
    width: 100%;
    min-height: 60vh;
    transition: background-color var(--transition), border-color var(--transition);
}

.w-full {
    width: 100%;
}

.flex {
    display: flex;
}

.flex-col {
    flex-direction: column;
}

.justify-between {
    justify-content: space-between;
}

.justify-center {
    justify-content: center;
}

.items-center {
    align-items: center;
}

.items-start {
    align-items: flex-start;
}

.gap-2 {
    gap: 0.5rem;
}

.gap-3 {
    gap: 0.75rem;
}

.gap-4 {
    gap: 1rem;
}

.mb-1 {
    margin-bottom: 0.25rem;
}

.mb-2 {
    margin-bottom: 0.5rem;
}

.mb-4 {
    margin-bottom: 1rem;
}

.mb-6 {
    margin-bottom: 1.5rem;
}

.mt-2 {
    margin-top: 0.5rem;
}

.mt-4 {
    margin-top: 1rem;
}

.mt-auto {
    margin-top: auto;
}

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

.text-sm {
    font-size: 0.875rem;
}

.text-xs {
    font-size: 0.75rem;
}

.text-lg {
    font-size: 1.125rem;
}

.text-xl {
    font-size: 1.25rem;
}

.text-2xl {
    font-size: 1.5rem;
    font-weight: 600;
    letter-spacing: -0.02em;
}

.font-semibold {
    font-weight: 600;
}

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

.text-muted {
    color: var(--text-secondary);
}

.hidden {
    display: none !important;
}

/* Navigation */
.nav-btn {
    background: none;
    border: none;
    color: var(--text-secondary);
    font-size: 1.5rem;
    cursor: pointer;
    padding: 0.25rem 0.5rem;
    border-radius: var(--radius-md);
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
}

.nav-btn:hover {
    color: var(--text-primary);
    background-color: var(--border-color);
}

.date-header {
    text-align: center;
    flex-grow: 1;
    font-size: 1.125rem;
    font-weight: 500;
}

.paper-date-header {
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 1rem;
    margin-bottom: 2rem;
    font-size: 1.5rem;
    font-weight: 600;
    letter-spacing: -0.02em;
    color: var(--text-primary);
    display: flex;
    justify-content: space-between;
    align-items: flex-end;
}

.paper-date-header .date-sub {
    font-size: 1rem;
    font-weight: 400;
    color: var(--text-secondary);
}

/* Forms */
label {
    display: block;
    font-weight: 500;
    color: var(--text-primary);
    margin-bottom: 0.35rem;
    font-size: 0.875rem;
}

input[type="text"],
input[type="password"],
select {
    width: 100%;
    padding: 0.6rem 0.8rem;
    background-color: transparent;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-family: inherit;
    font-size: 0.95rem;
    transition: var(--transition);
}

input:focus,
select:focus {
    outline: none;
    border-color: var(--accent-color);
    background-color: var(--bg-color);
    /* Slight fill on focus */
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 1rem 2.5rem;
    /* ability.icu style padding */
    font-weight: 600;
    /* Bolder text */
    border-radius: 50px;
    /* Fully rounded */
    border: 1px solid transparent;
    cursor: pointer;
    transition: transform 0.2s ease, background-color 0.2s ease, color 0.2s ease;
    font-family: inherit;
    font-size: 1rem;
}

.btn:hover {
    transform: translateY(-2px);
}

.btn-primary {
    background-color: var(--accent-color);
    color: #ffffff;
}

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

.btn-outline {
    background-color: transparent;
    border-color: var(--border-color);
    color: var(--text-primary);
}

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

.btn-sm {
    padding: 0.35rem 0.75rem;
    font-size: 0.8rem;
}

/* States */
.error-box {
    background-color: var(--error-bg);
    color: var(--error-text);
    border-radius: var(--radius-md);
    padding: 1rem;
    font-size: 0.875rem;
    font-weight: 500;
}

/* Modal / Settings Overlay */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: rgba(0, 0, 0, 0.4);
    backdrop-filter: blur(2px);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 50;
    opacity: 0;
    pointer-events: none;
    transition: opacity var(--transition);
}

.modal-overlay.active {
    opacity: 1;
    pointer-events: auto;
}

.modal-content {
    background-color: var(--surface-color);
    border-radius: var(--radius-lg);
    padding: 2rem;
    width: 90%;
    max-width: 400px;
    box-shadow: var(--shadow-paper);
    transform: scale(0.95);
    transition: transform var(--transition);
    border: 1px solid var(--border-color);
}

.modal-overlay.active .modal-content {
    transform: scale(1);
}

/* Loading Spinner */
.spinner {
    animation: spin 1s linear infinite;
    color: var(--accent-color);
    width: 2rem;
    height: 2rem;
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}