:root {
  font-size: 16px;
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  color-scheme: dark light;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  background: var(--color-bg);
  color: var(--color-text);
  transition: background 0.3s ease, color 0.3s ease;
}

body[data-theme="dark"] {
  --color-bg: #10131a;
  --color-surface: #171c26;
  --color-border: #262c3b;
  --color-text: #f4f7ff;
  --color-text-muted: #9ba4bf;
  --color-primary: #5c8dff;
  --color-primary-hover: #7aa3ff;
  --color-danger: #ff6f6f;
  --color-danger-hover: #ff8a8a;
  --shadow-elevated: 0 24px 40px -20px rgba(12, 16, 24, 0.6);
}

body[data-theme="light"] {
  --color-bg: #f5f7fb;
  --color-surface: #ffffff;
  --color-border: #d7dce5;
  --color-text: #1f2430;
  --color-text-muted: #4b556b;
  --color-primary: #325dff;
  --color-primary-hover: #5a7cff;
  --color-danger: #d64545;
  --color-danger-hover: #f25d5d;
  --shadow-elevated: 0 24px 40px -24px rgba(27, 42, 93, 0.3);
}

a {
  color: inherit;
}

.app {
  max-width: 960px;
  margin: 0 auto;
  padding: 3rem 1.5rem 4rem;
  display: flex;
  flex-direction: column;
  gap: 2.5rem;
}

.app__header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1.5rem;
  flex-wrap: wrap;
}

.app__title {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.app__title h1 {
  margin: 0;
  font-size: clamp(1.75rem, 4vw, 2.25rem);
}

.app__title p {
  margin: 0.35rem 0 0;
  color: var(--color-text-muted);
  font-size: 0.95rem;
}

.app__icon {
  width: 48px;
  height: 48px;
  flex-shrink: 0;
  filter: drop-shadow(0 8px 16px rgba(0, 0, 0, 0.22));
}

.theme-toggle {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.35rem 1rem 0.35rem 0.35rem;
  border-radius: 999px;
  border: 1px solid var(--color-border);
  background: var(--color-surface);
  color: var(--color-text);
  cursor: pointer;
  transition: background 0.3s ease, border-color 0.3s ease;
}

.theme-toggle:focus-visible {
  outline: 3px solid var(--color-primary);
  outline-offset: 3px;
}

.theme-toggle__thumb {
  display: block;
  width: 34px;
  height: 34px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-hover));
  box-shadow: 0 12px 24px -12px rgba(20, 70, 255, 0.8);
  transition: transform 0.3s ease;
}

body[data-theme="light"] .theme-toggle__thumb {
  transform: translateX(110%);
  background: linear-gradient(135deg, #ffd15c, #ffb347);
  box-shadow: 0 12px 24px -12px rgba(255, 179, 71, 0.8);
}

.theme-toggle__label {
  font-weight: 600;
  font-size: 0.95rem;
}

.app__main {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 2rem;
}

.entry-form,
.entries {
  background: var(--color-surface);
  border-radius: 20px;
  padding: 2rem;
  box-shadow: var(--shadow-elevated);
  border: 1px solid var(--color-border);
}

.entry-form h2,
.entries h2 {
  margin: 0 0 1.5rem;
  font-size: 1.4rem;
}

.form__label {
  display: block;
  font-weight: 600;
  margin-bottom: 0.5rem;
}

.form__input,
.form__textarea {
  width: 100%;
  padding: 0.75rem 1rem;
  border-radius: 14px;
  border: 1px solid var(--color-border);
  background: rgba(0, 0, 0, 0.1);
  background: color-mix(in srgb, var(--color-surface) 82%, #ffffff 18%);
  color: inherit;
  font-size: 1rem;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
  resize: vertical;
}

.form__input:focus,
.form__textarea:focus {
  border-color: var(--color-primary);
  outline: none;
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--color-primary) 30%, transparent);
}

.form__textarea {
  min-height: 170px;
}

.form__actions {
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
  margin-top: 1.5rem;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.35rem;
  padding: 0.7rem 1.4rem;
  border-radius: 999px;
  border: 1px solid transparent;
  font-weight: 600;
  font-size: 0.95rem;
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease,
    border-color 0.2s ease;
}

.button:focus-visible {
  outline: 3px solid color-mix(in srgb, var(--color-primary) 70%, #ffffff);
  outline-offset: 3px;
}

.button--primary {
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-hover));
  color: #ffffff;
  box-shadow: 0 14px 24px -18px var(--color-primary);
}

.button--primary:hover {
  transform: translateY(-1px);
}

.button--ghost {
  background: transparent;
  border-color: var(--color-border);
  color: inherit;
}

.button--ghost:hover {
  border-color: color-mix(in srgb, var(--color-border) 40%, var(--color-primary));
}

.button--danger {
  background: transparent;
  border-color: color-mix(in srgb, var(--color-danger) 60%, var(--color-border));
  color: var(--color-danger);
}

.button--danger:hover {
  background: color-mix(in srgb, var(--color-danger) 12%, transparent);
  border-color: var(--color-danger-hover);
  color: var(--color-danger-hover);
}

.entries__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.entries__placeholder {
  padding: 1.5rem;
  border-radius: 18px;
  background: color-mix(in srgb, var(--color-surface) 90%, #ffffff 10%);
  border: 1px dashed var(--color-border);
  text-align: center;
  color: var(--color-text-muted);
}

.entry {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1rem;
}

.entry__card {
  background: color-mix(in srgb, var(--color-surface) 92%, #030711 8%);
  border-radius: 18px;
  padding: 1.5rem;
  border: 1px solid color-mix(in srgb, var(--color-border) 86%, #ffffff 14%);
  box-shadow: 0 18px 30px -24px rgba(0, 0, 0, 0.7);
}

.entry__header {
  display: flex;
  justify-content: space-between;
  gap: 0.75rem;
  align-items: baseline;
  flex-wrap: wrap;
}

.entry__date {
  margin: 0;
  font-size: 1.15rem;
}

.entry__meta {
  margin: 0;
  color: var(--color-text-muted);
  font-size: 0.85rem;
}

.entry__text {
  margin: 1rem 0 0;
  line-height: 1.6;
  white-space: pre-wrap;
}

.entry__actions {
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
}

@media (max-width: 900px) {
  .app__main {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 600px) {
  .app {
    padding: 2.5rem 1.1rem 3rem;
  }

  .entry-form,
  .entries {
    padding: 1.5rem;
  }

  .form__actions {
    flex-direction: column;
    align-items: stretch;
  }

  .button {
    width: 100%;
  }

  .theme-toggle {
    width: 100%;
    justify-content: space-between;
  }

  .entry__header {
    align-items: flex-start;
    flex-direction: column;
  }
}